The present invention is relating to an integrated circuit package, particularly to an integrated circuit package with micro BGA configuration.
In the integrated circuit packaging industry, it is a trend that a lead frame being as a die carrier has been displaced by a wiring substrate, such as BGA substrate (Ball Grid Array substrate) that generally is to adhere a die on a surface of BGA substrate and to bond solder balls on another surface of wiring substrate for surface mounting.
An integrated circuit package with micro BGA configuration is disclosed in U.S. Pat. No. 5,776,796 xe2x80x9cmethod of encapsulating a semiconductor packagexe2x80x9d. As shown in FIG. 1, a semiconductor die package 10 comprises a semiconductor die 12 and a die carrier 14. The die carrier 14 is composed of a dielectric layer 16 and a spacer layer 20 with elasticity. A plurality of leads 22 electrically connect the semiconductor die 12 with the dielectric layer 16 of die carrier 14 made from a thin sheet of polyimide, so that the semiconductor die 12 can electrically connect to the terminals 26 on the top surface 18 of the die carrier 14. The semiconductor package 10 is set in a frame 42, a cover 30 is attached below the frame 42, and the cover 30 attaches the top surface 18 of die carrier 14 for protecting the terminal 26 during encapsulating. Next, the introduction of package body 40 may carry out by using needle-like dispenser 32. Comparing naturally potting method with molding technique, the leads 22 form many tiny apertures between die 12 and dielectric layer 16 so that gas bubbles are easy to be formed, otherwise a vacuum laminating is necessary. Moreover, the shape of solidified package body 40 has no mechanically fastening function but adhesive function against the die carrier 14. Moisture will permeates into the interface between the package body 40 and the dielectric layer 16. The bonding strength between semiconductor die 12 and die carrier 14 becomes weaker resulting in delamination or popcorn easily.
A first object of the present invention is to provide an integrated circuit package with excellent bonding strength between wiring board and chip without delamination happen. A package body has a fastener extending around the lateral surfaces of the wiring board to hold wiring board.
A second object of the present invention is to provide an integrated circuit package, which comprises a wiring board having support bars. The support bars allow an extending fastener of package body to be formed around the lateral surfaces of wiring board for forming a well-bonded package body by molding method. The extending fastener prevents moisture from penetrating into the lateral surfaces of wiring board.
In accordance with the integrated circuit package of the present invention, it comprises a wiring board having a die-attaching surface, a surface-mounting surface and lateral surfaces between the die-attaching surface and the surface-mounting surface. Preferably, the wiring board has a plurality of support bars for supporting the wiring board during molding. A die having a plurality of bonding pads is adhered on the die-attaching surface of wiring board. The bonding pads of die are electrically connected with the wiring board by a plurality of metal bonding wires. A package body formed by molding seals the metal bonding wires and has an extending fastener around the lateral surfaces of the wiring board for holding the wiring board.